HI,I'm about to buy a new MoBo, athlon XP and some RAM - I thought I had a fairly good knowledge of hardware but the more I read it seems the less I know. btw I use my PC mainly for gaming and video editing.

I don't understand all this stuff about syncronous and async and fsb and RAM speed and stuff like that - I'm not looking at overclocking.

So I was thinking of buying an XP2500 or XP2600 processor and possibly a Gigabyte GA-7N400-L1 or Asus A7N8X Motherboard. And I'm not sure what speed RAM to get and what this Double DDR thing is.

If someone has a few minutes to explain to me about the RAM and what MoBo they think I should get I would be very thankful.

If you're getting a 333MHz CPU, I suggest getting some PC3200 DDR RAM, then running it at 333 with the CPU. Don't scrimp on the RAM, get some good stuff like Corsair XMS. If you get the latest revisions of the NForce MB's they will be fully compatable with 400FSB processors too, so consider that. I'm running a XP2600(333) here with no problems, but it's also running at 2.3 instead of 2.1 GHz, which is a moderate O/C. Running in "synch" simply means that you're running the RAM at the same speed as the CPU. This is a lot faster than running it "asynch". An example would be the above situation. If you install PC3200 RAM and let the board set the speed, it'll be running asynch, (400). So you go into BIOS and set it to run at 333, or 100% (synch). Since you're using DDR memory, the actual FSB speed will be 166MHz in the BIOS. DDR memory is fairly finicky, a lot of what is rated at 333 isn't all that great at that speed, and can cause instability issues. this is why I recommend getting PC3200. Although if you get the good stuff, PC2700 should work well enough too. It's just that getting PC3200 gives you some future compatability with the 400FSB processors.

Dual channel, in theory, gives you a slight advantage. I've never bothered to compare single channel with dual on this board, I don't see a reason to. I wanted 1024MB, and 2 x 512 is the only reasonable way to get it. Price considerations aside, there's no reason to get one stick of 512 if you can get 2 x 256 and run dual channel. I've never seen any testing of the "real-world" difference.

So called matching pair RAM are marketing hype to trick people into believing they handpicked and tested each pair of RAM for max OC, which is bull 'cause you can do the samething by just buying 2 identical sticks (make and model) separately and have the same result.

If you're using PC3200 RAM and a nForce2 mobo that officially supports 400FSB, get a Barton 2500+ CPU, get into mobo BIOS and set the CPU FSB to 200, FSB/DRAM Radio to 1:1, and you'll see DRAM Clock auto change to 200. If not, manually change the DRAM clock to match the CPU FSB. You'll get the best performance this way.

I've seen quite some tests on the single/dual channel ram issue with the NF2 chipset. It seems that every tests has really different results. Although the differences aren't huge, I sometimes am surprised when I see that single channel beats dual channel.

My suggestion: get 2 sticks and if you're interested, do some real-life benchmarking!

Like most things with RAM, actual performance can vary a lot from theoretical performance. The amount of RAM makes a big difference too, the more you have the slower it is. But I'll take large amounts of slower RAM any day, over smaller amounts of faster RAM. It also follows that the process of managing dual channel might consume as much of the "throughput" as is gained by the dual-channel mode. A lot depends on how it's implemented by the board, and even more depends on the person who sets it up. We all know that running RAM out of synch, even at 1.5x the CPU speed, will actually lower RAM benchmarks. Maybe next time I'm inside there, I'll swap one stick into the other slot and try it in single channel mode just for fun.